Thermostat for fire-alarms



* (No M l.) 2 Shetssheet 1.

' J. J. BYRNE.

VTHERMOSTAT FOR FIRE ALARMS. No. 322,417. Patented July 21, 1885.

2 Sheets-Sheet 2.

.Z "IG .3.

INV ENTOR (No Model.)

J. J. BYRNEQ THERMOSTAT FOR FIRE ALARMS.

No. 322,417. Patented July 21, '1885.

ATTESTZ UNITED STATES PATENT OFFICE.

JOHN J. BYRNE, OF OHIOAGO,.ILLINOIS.

THERMO'STAT FOR FIRE-ALARMS.

B'PECIFICATION forming part of Letters Patent No. 322,417, dated July21, 1885.

Application filed February 27, 1885.

To all whom, itmay concern.-

Be it known that I, JOHN J. BYRNE, a citizen of the United States, and aresident of Chicago, in the'county of Cook and State of Illinois, haveinvented certain new and useful Improvements in Thermostats for Fire-Alarms, 8E0. and I dohereby declare the following to be a full, clear,and exact description of the same, reference being had to theaccompanying drawings, forming a part of this specification.

This invention relates to that class of thermostats for fire-alarm andother purposes in which a bar or body of metal or other suitablematerial is employed, the expansion of which, by an increase oftemperature, acts to release a suitable alarm mechanism or make anelectric connection and indicate or sound an alarm; and this inventionhas for its objects, first, to provide a simple, cheap, and verysensitive form of thermostat for making either an elec tric connectionor releasing a train of alarmgearing; second, to afford a simple andeffective mechanism for releasing a train of gearing to give an alarm;third, to provide means for throwing out of gear the escapement-wheeland its driving-connections after the train of alarm-gear has beenreleased; fourth, to furnish an improved arrangement for operating theindex or pointer that indicates the temperature to which the thermostatis exposed,

and which also serves as a guidein setting the apparatus to give analarm when a predetermined temperature is reached; and, fifth, tofurnish a simple and effective means for set ting or adjusting thereleasing mechanism so that an alarm will be given when a predeterminedtemperature is reached. I attain such objects by the construction andarrangement of parts illustrated in the accompanying drawings, in which'I Figure 1 is a front elevation illustrating my improvements adapted toa single-acting me chanical fire-alarm; Fig. 2, a similar View, withparts of the casing removed; Fig. 3, a transverse section of same; Fig.4, a rear elevation of the frame of the driving-gear, showing theoperating-spring and the mechanism for ringing the alarm-bell; Fig. 5,an enlarged detail elevation of the indicator dial and pointer and (Nomodel.)

the means for operating the same; Fig. 6, an enlarged transverse sectionof the same; Fig. 7,

a detail elevation of a modified formof the releasing mechanism, andFig. 8 a longitudinal sectional elevation illustrating my improve' mentarranged as an electric thermostat.

Similar letters of reference indicate like parts in the several views.

My invention, in the main, relates to the con struction and arrangementof the thermostat A, which, in the present improvement, consists of abar or rod, A, slightly bowed or arched, as shown, and secured at eachend to'fixedabutments B B.

The thermostatic bar A is made of some thickness at its ceuterand taperstoward its ends, as shown, as I find that such formof bar is assensitive as a thin strip of uniform thickness, andat the same timecauses the bar to retain its proper bow or arched shape under thevarying conditions as to temperature and strain to which it is exposed.

The manner of connecting the ends -of the thermostatic bar A to theabutments B is as follows: I provide the bar A with an eye, a, at eachend to engage a stud or pin, b, on the abutments B. It is alsopreferable to make one of the abntments B adjustable, asindicated inFig. 2, so as to effect the preliminary adjustment of the bar A inputting the parts together.

In nseI prefer to form the thermostatic bar A of hard rubber, vulcanite,or analogous ma terial, as I find by practical experiment that suchsubstances possess expansive properties of a very high order.

O is the escapementreleasing bar or rod, moving in suitable guides,asshown, and con nected to the center or crown of the arched thermostaticbar A,its end engaging in a notch, 0 d, in the escapement wheel or diskD, which is in connection with a train of driving-gear, (see Fig. 2,)the connection being, by pinions and gears e E e Ee E c with the shaftof the driving-gear E, that receives motion from a spring.

In the drawings I have shown a plate or leaf spring,F,for impartingmovement to thetrain of gearing, yet I do not limit my invention to suchform of spring, as a volute or other form of spring may be employedinstead to attain a like result. 7

"c is athumb-nut upon the screw-threaded portion of the rod C, to forman adjustable rest for said rod upon the thermostatic bar A, the purposebeing to regulate the depth of the engagement of the end of said rod inthe notch d of the escapement-wheel D, and consequently the degree oftemperature required to withdraw said rod from such notch and releasethe escapement-wheel.

WVhile I prefer to make connection between the rod 0 and theescapement-disk D direct, yet, in cases wherea more sensitivearrangement is required, the rod can act through a sp1'ing-lever,O,t0lock or engage said disk, as indicated in Fig. 7. The driving-gear Bwill be secured to its shaft by a ratchet-wheel and pawl (not shown) inmanner usual. to clocks, &c., so as to admit of the winding up of thespring when required.

In order to throw the eseapementdisk D, with its driving pinion and gear6 E, out of engagement with the rest of the train of gearing after thesame has been released, I make the pinion c of a mutilated form, asshown in Fig. 2, so that after a certain amount of rotation has beenimparted to the escapementwheel the parts will move out of engagement,and thus remove a portion of the work or re sistance to be overcome bythe spring, and leaving it free to expend its entire force in ringingthe alarm-bell G,which is arranged at the back of the supporting-frameof the train of gearing, its striker 9 being operated by aratchet'wheel, G, upon the shaft of the gearwheel and pinion E 6 asindicated in Fig. 4E.

The dial or indicator for indicating the temperature to which theapparatus is exposed consists of adial, H, secured to the post or studit, upon which the gear and pinion E 6 turns, and a hand or pointer, i,secured to an arbor or spindle, I, turning in said post, as

' clearly indicated in Figs. 2, 3, 5, and 6, mo-

tion being communicated to said spindle by a cord or wire, t", whichengages in a circumferential groove in said spindle, and has one endconnected to the escapemei'it-releasing bar 0, and the other end to aspring,J, as clearly indicated in Figs. 2 and 5.

J is a temper-screw bearing against the spring J, and by means of whichthe tension or movement of the spring is regulated and adjusted. By thisconnection of parts it will be seen that the spring, in addition tokeeping the cord or wire z taut, also acts to keep the eseapement-bar (Jin contact with the thermostat A.

In Fig. 8 I illustrate my invent-ion arranged as an electric thermostatfor making, on a predetermined increase of temperature, an electricconnection, so as to send an alarm. In this the arched thermostatic barA is preferably arranged within a casing, A, of glass, in order that itmay be hermetically sealed so as to exclude dust, &c., and is providedwith metallic contacts a aflplaced in the electric circuit, asindicated.

A is a metallic housing or casing to receive and hold the glass casing Aand furnish means for securing the apparatus in place upon a wall orceiling of a building.

WVhile in the drawings I have shown the thermostatic bar A arrangedsingly, yet it is evident that a'pair of the same can be used inconjunction and arranged in reversed directions to each other. 111 thiscase the one bar would carry the alarm mechanism, and the other operatethe eseapement-releasing bar 0; and in the case of the electricthermostat the one would carry one electric pole, and the other theopposite electric pole. It is also evident that the mechanical alarmapparatus can be so arranged as to transmit an alarm to some centralstation, as well as giving a local alarm at the place where it islocated, by means of wire and bell-crank connections from the localapparatus to a main central apparatus, where the alarm is again givenand recorded.

Having thus fully described my invention, what I claim as new, anddesire to secure by Letters Patent, is

1. A thermostat for fire-alarms, &c., consisting of an arch-shaped bar,A, provided with eyes a, and arranged between fixed abutments B,provided with pivot-pins b for the eyes a, substantially as set forth.

2. A thermostat for fire-alarms, &c., consisting of a bar, A, thickenedat its center and, tapering toward its ends, in combination with fixedabutments B B for confining the ends of said bar, substantially as setforth.

3. A thermostat for fire-alarms, &c., consisting of an arch-shaped bar,A, of hard rubber or other analogous material, provided with eyes a, incombination with fixed abutments B B, provided with journal-pinsZ),substantially as set forth.

4. The combination, in a fire-alarm, of a train of gears provided with astriking mechanism, and an cscapement-disk, D, with the archedthermostat A, fixed abutments B B, and escapement-releasing bar 0,substantially as set forth.

5. The combination, in a fire-alarm, of the arch-bar A, abutments B B,rod 0, adjustable thumb-nut c, and the eseapement-disk D of a train ofalarm-gear, essentially as and for the purpose set forth.

6. The combination of the arched thermostat A, fixed abutments B B, andbar 0 with cord or wire 71, spindle I, spring J, pointer i, and dial H,substantially as and for the purpose set forth.

7. The combination of the arched thermostat A, having fixed abutments BB, with the bar 0, cord 4;, spindle I,vspring J, temperscrew J, pointert, and dial H, substantially as and for the purpose set forth.

8. In a fire-alarm apparatus, essentially as set forth, the fixed studh, forming a journal for the gear and pinion E e, and provided drivenpinion, e, inserted between the alarm- 10 with an axial recess for thespindle I, in 00111- striker and the escapement device, essentiallybination with the pointer 13, dial H,seoured to as described.

said stud, and means,essentia11y as herein de- In testimony whereofwitness my hand this seribed,for operating. said pointer. 23d day ofFebruary, 1885.

9. In a fire-alarm apparatus, essentially as JOHN J. BYRNE. set forth,the combination of a train of driv- In presence of ing-gear, analarm-bell striker, and an escape- ROBERT BURNS,

ment device, in combination with a mutilated M. E. BYRNE.

